Updates to support DokuWiki rc2013-10-28 "Binky"

The introduced LESS support [1] stumbled upon several CSS hacks for older
Internet Explorer versions. This commit puts these hacks in a separate file
which gets loaded by a simple conditional comment instead of the style.ini.
So only older MSIE clients but not DokuWiki itself gets faced with the hacks.

[1] <https://github.com/splitbrain/dokuwiki/pull/240>